There are conventionally known vehicle lighting fixtures to be mounted on a vehicle body having a plurality of light sources such as light emitting diodes arranged, for example, those described in Japanese Patent Application Laid-Open No. 2001-266620 (or U.S. 2001/0019486 A1 corresponding thereto). In recent years, variable light distribution type headlamps that can change its light distribution according to the surrounding environment have been widespread. In general, this type of vehicle lighting fixture can be configured to include a number of light emitting diodes that can be independently controlled to be turned ON/OFF.
When a plurality of light sources are arranged, it is absolutely difficult to dispose the plurality of light sources without any gap therebetween. Thus, if such a plurality of light sources with a gap therebetween are turned on, the irradiation area may include darkened areas due to the gaps between the adjacent light sources, thereby resulting in light intensity unevenness in the produced light distribution pattern. When such a vehicle lighting fixture is used as a headlamp or a signal light, there may be a case of lowering the visibility of a driver or misunderstanding of driving conditions by a driver. This results in destructing the safety of driving.
To cope with this problem, Japanese Patent Application Laid-Open No. 2006-522440 (or U.S. 2006/0198118 A1 corresponding thereto) describes a vehicle lighting fixture in which a number of semiconductor light sources arranged on a substrate are covered with a light-transmitting chip cover. Furthermore, the chip cover is filled with a light-scattering and/or light-converting auxiliary material. As a result, the light from the semiconductor light sources can be diffused by the auxiliary material, to thereby suppress the light intensity unevenness in the light distribution.
However, the vehicle lighting fixture of Japanese Patent Application Laid-Open No. 2006-522440 (or U.S. 2006/0198118 A1 corresponding thereto) utilizes the diffusion function of light by the auxiliary material, it is difficult to control the degree of diffusion. Thus, when the disclosed vehicle lighting fixture is applied to a variable light distribution type headlamp, the light from the turned-on light source may be unintentionally directed in an optical path from a turned-off light source. In this case, an accurate light control may be hindered.